A set-top box (STB) is typically provided by a multiple-system operator (MSO) to a subscriber so that the subscriber may receive multimedia services offered by the MSO. The STB can be used by the subscriber to access a variety of multimedia services, including but not limited to live or linear television, digital video recorder (DVR) content, video-on-demand (VoD) content, over-the-top (OTT) content, and others.
Generally, in order to process and output a piece of multimedia content, a STB needs to be able to identify and decode information associated with the multimedia content that is delivered to the STB. For example, audio and video information associated with a piece of multimedia content may be delivered to a STB as one or more elementary streams of a transport stream, and the STB may retrieve information from a program map table (PMT) carried by the transport stream in order to identify and decode the audio and video information. A PMT (e.g., PMT of a Moving Picture Experts Group (MPEG) transport stream) may include information associated with a channel or program such as audio packet identifiers (PIDs), video PIDs, program clock reference (PCR) PIDs, data PIDs, metadata associated with the channel or program, and other information.
Typically, a STB will acquire a PMT according to a predetermined PMT polling period. However, when an audio/video transition occurs (e.g., channel change, targeted advertisement (TAD) switch, changes to current audio PIDs or video PIDs, changes to audio/video parameters, and/or other conditions or events), new audio/video information may be received at the STB in between PMT acquisitions, and without the PMT information associated with the new audio/video information, the STB may be unable to immediately retrieve and process the new audio/video information. After an audio/video transition, and before a new PMT is acquired by the STB, a viewer may miss portions of the multimedia content that is being requested from the STB. Therefore, it is desirable to improve upon methods and systems for retrieving PMT information after an audio/video transition.
Like reference numbers and designations in the various drawings indicate like elements.